Project Summary/Abstract: The goal of this proposal is to acquire funds to purchase a Scanco <CT40 instrument for 2- and 3-dimensional imaging and quantitative analyses of trabecular and cortical bone properties of small animal (mouse and rat) models. This instrument is to be shared among 15 users (10 are supported by 14 NIH grants, and 5 are recently recruited junior faculty). There is no similar instrument available on the UMASS Medical School, Worcester campus and at present sixteen research programs are in need of this for quantitative assessment of skeletal abnormalities in genetic mouse models, addressing novel therapeutic approaches for osteoarthritis and defects in fracture repair, characterization of new biomaterial substitutes for bone repair, and novel approaches for protecting the bone from irradiation damage and the osteolytic destruction caused by tumor growth in bone. Currently, these projects use multiple methods including standard radiography, magnetic resonance imaging, and histology to assess tissue structure and tissue healing. Micro-computed tomography adds an important dimension to this existing armamentarium by providing capabilities for detailed characterization of bone tissue by quantitative measurements such as bone mineral density, trabecular and cortical thickness, bone porosity and other parameters that reflect bone formation and resorption. The <CT data is critical in elucidating relationships between bone structure and function in both healthy and diseased tissues. The nondestructive nature of <CT imaging allows subsequent analysis of a single specimen by any number of complimentary techniques, including histology and mechanical testing. Thus, use of <CT does not require an increase in specimen or animal numbers. Our previous use of <CT has been limited by access to this instrumentation, rather than the utility of this technology for our research. A goal in obtaining the <CT is to facilitate translational research that is a major direction of the UMASS Medical campus in basic research and clinical investigations are becoming well integrated in the areas or skeletal biology and cancer research. The high-resolution desktop <CT system requested in this application will be fully utilized by a team of investigators who have a strong track record of providing important results, as well as new research directions in skeletal healing, osteoporosis, osteoarthritis and metastatic bone disease. [unreadable] [unreadable] [unreadable]